WPI EVOM - Troubleshooting

36 World Precision Instruments
TROUBLESHOOTING
EVOM™ Manual Meter: Most of the time, system problems are related to the
electrode, not the meter itself.
Some issues you may encounter include:
• UNSTABLE OR HIGH READING: If the electrode fails, the most common symptom
is an unstable or unusually high reading.
• LOW RESISTANCE: When the meter displays a lower than expected resistance, but
is stable and reproducible, the most likely cause is related to the cell culture, not
necessarily the meter or the electrodes.
Issue
Possible Cause Solution
Unit runs briey, and powers o
Unit is
insuciently
charged
Recharge the unit for at least 12 hours.
NOTE: Make sure the EVOM™ Manual is powered o
when charging the battery.
Unit does not
charge or charging
LED not lit
Insecure
connection at
power input jack
on meter
Verify that the power connector is securely connected
at the meter power input jack.
Defective charger The EVOM™ Manual charge socket can be tested with a
USB to Mini-B cable plugged into a computer’s USB port
(WPI #803026). If the charging LED lights up, then a new
charger is needed (WPI #803025).
USB drive not working /not recognized
Not all USB ash
drives work on
the EVOM™
Manual.
See "Sample Resistance File (*.csv)" on page 23 and
page 5.
Meter will not power
on with charger
DISCONNECTED
Batteries are
discharged
The meter powers down automatically when the
batteries are depleted. Power o the meter and
connect it to the battery charger. Charge it for at least
12 hours. A full charge may require up to 24 hours. For
reliability, the meter should be charged each evening
(with the power o) before use the next day.
Batteries are
defective
Contact WPI for service. The EVOM™ Manual battery is
not user serviceable.